Synthesis of alpha-keto-imides via oxidation of ynamides.
A de novo preparation of alpha-keto-imides via ynamide oxidation is described. With a number of alkyne oxidation conditions screened, a highly efficient RuO2-NaIO4 mediated oxidation and a DMDO oxidation have been identified to tolerate a wide range of ynamide types. In addition to accessing a wide variety of alpha-keto-imides, the RuO2-NaIO4 protocol provides a novel entry to the vicinal tricarbonyl motif via oxidation of push-pull ynamides, and imido acylsilanes from silyl-substituted ynamides. Chemoselective oxidation of ynamides containing olefins can be achieved by using DMDO, while the RuO2-NaIO4 protocol is not effective. These studies provide further support for the synthetic utility of ynamides.
Al-Rashid
Ziyad F
ZF
Division of Pharmaceutical Sciences and Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53705, USA. zalrashid@alchemicalresearch.com
Johnson
Whitney L
WL
Hsung
Richard P
RP
Wei
Yonggang
Y
Yao
Pei-Yuan
PY
Liu
Renhei
R
Zhao
Kang
K
D000480:Alkynes / Q000737:chemistry*; D007094:Imides / Q000138:chemical synthesis* / Q000737:chemistry; D007659:Ketones / Q000737:chemistry*; D010084:Oxidation-Reduction; D013379:Substrate Specificity
D000480:Alkynes; D007094:Imides; D007659:Ketones